Users of today's database systems can generate database models of real-world objects of considerable complexity. These objects can be hierarchical structures including hundreds and even thousands fields. One recurring task in operating a database system consists in mapping fields of multiple first database objects onto fields of a second database object. For instance, a user of a database system might wish to unify a first database object including last year's sales data and a second database object including this year's sales data into a new database object “overall sales data.” To do so, the user maps the fields of the first and second (source) database objects to corresponding fields of the new (target) database object. During or after this procedure, the user might want to check if the database objects are properly mapped. Database systems can provide a visual representation of the mapped database structures based on which the user can check proper mapping. However, as the source and the target database objects can each involve hundreds or thousands of fields, checking the correct mapping can be cumbersome. In addition, graphically representing large hierarchical structures and their mappings (e.g., on a display of a user device) can require a substantial amount of computer resources. Therefore, the checking procedure might involve delays and latencies as, e.g., the user device might require perceptible amounts of time to retrieve and render representations of the database objects and their mappings.